Hammer action for musical instruments



J. D. ENOCHS ETAI'.

HAMMER ACTION FOR MUSICAL INSTRUMENTS June 9, 1953 med oct. 2e, 1948 POF f77 EQU/f//l/ ,L7 Trae/Ufff'.

June 9, 1953 J. D. ENocHs ErAL HAMMER ACTION FOR MUSICAL INSTRUMENTS 2 Sheets-Sheet 2 Filed Oct. 26, 1948 IN VEN TORS. E/l/OC'HS ./7. BA? Old/U .fEeO//E for Y Patented `une 9, 1,953

HAMMER ACTION FOR MUSICAL INSTRUMENTS Jerome D. Enochs, Bronx, and Roy M. Brown, Brooklyn, N. Y., assignors to Jaymar Specialty Company, Brooklyn, N. Y., a partnership .Application rvOctoberZG, 1948, Serial N o. 56,532

(Cl. SLi-403) 16 claims. l

This .invention relates to .musical instruments, and more particularly to a toy piano.

The primary object of the present invention is to generally improve toy pianos. A more particular object is to .provide a simplified key and hammer action. .Another object is to .design the parts for ease of assembly, thereby decreasing labor cost in manufacture of the instrument. More specific objects are to improve the pivoting of the hammer on the key, and the pivoting of the key in the instrument. Further objects are to improve the means for guiding vand llocating 'the keys, and for .limiting the motion thereof.

To accomplish the foregoing general objects, and other more specific objects which will hereinafter appear, our .invention resides in the toy piano elements and Vtheir relation one to another as are hereinafter more particularly described in the following speccation. The speci-cation Vis accompanied by drawings in which.:

Fig. l is a perspective view showing .a .toy piano embodying features of the present i-nvention;

Fig. 2 is a fragmentary .plan view with apart of the case kbroken away;

Fig. 3 is a section taken approximatel-y in the plane of the line 3 3 of Fig. 2;

Fig. 4 is a section taken approximately in the plane of the .line 4 4 of Fig. 2, with a black key depressed;

Fig. 5 is a Vsection through the .hammer .taken approximately yin the plane of the line 5 5 of Fig. 4;

Fig. 6 is a fragmentary section taken approximately in the `plane of the line .6 6 of Fig. 3;

Fig. 'I is a section taken approximately in the plane of the line 1 1 of Eig. 3;

Figs. 8, 9 and l0 are schematic sections taken approximately in the plane of the line 8 8 of Fig. 43 and are explanatory of the key action.

Fig. 11 is a side .elevation of a modified key;

Fig. l2 isa section taken approximately in the plane of kthe'line I2 |2 of Fig. 1l; y

13 'is a fragmentary elevational view yof a modified fulcrum; and

lFig. 14 is a section through the same taken in the plane of the line M M.

Referring .to the drawing, and more ,particularly to Fig. l, the musical instrument .-is here illustrated as a toy piano of the spinet type. It will 'be understood that the key and hammer action may be applied to other musical instruments having sound-producing means different from -that .here shown, or :located in cases -of different configuration. However, the compactness of the hammer action, making Vit suitable fora spinet case, is one of its advantages. It should also be understood that the individual keys need not vbe .miniature in dimension, and in fact inthe particular `toy here shown the white and black keys are each of standard size, although the keyboard has only two and a half octaves.

Referring now to Fig. .3, the'key I2 has a rearward extension i4, and is pivoted at I6 ,intermediate the key and extension. 'The free end of the extension Il'. carries .a hammer I 8, the

yhead end 20 of which `extends towards the forward end of the key, and the tail end .2.2 of which extends beyond .the .pivot 24 of the hammer.. The sound producing means 26 is `disposed over the hammer, and a stop bar 2S is disposed above the tail 22 of the hammer. It will be evident that when the key is depressed the pivot 2li .is raised, thus raising the hammer head 2t to strike .the sound producing means 2'6.

Considering the arrangement in greater detail, another stop bar 3l] `is lpreferably disposed below 'the rear end 532 of key extension I4. The proportioningand disposition lof the `parts 'is such that when the key l2 is in raised position, the part S2 rests on .bar 39g, and the tail 22 rests (bearing upwardly) on bar 28. rThe latter contact limits the downward movement of the head 20, but is not essential because other motion limiting means might be employed, in which case the ltail 22 might be spaced downwardly from the bar 28 when the key is in rest position. The advantage of the present .arrangement is that cushioning material, specifically, strips of felt at v28 and 30, act as silencing means for the different movements. The head 2c does not hit or rest on the extension I4. This relationship or rest position is shown vin solid lines in Fig, 3. When the key .is depressed, Aas indicated in broken lines kin Fig. 3, the pivot 24 is raised, thus raising the hammer 2U, and the parts momentarily ltake a new position, rshown in broken lines. This relation of the parts is also shown 'in Fig. 9 of the drawing. However, the hammer head 2d `continues its upward movement under inertia andso strikes the sound producing means .26, as is best shown by the broken .line .position in Fig. 4. The relation of .the tail Aparts at this time is also shown in Fig. l0. After striking the .sound producing means and vsetting the same into vibration, .the hammer immediately V'falls back out of `the way to its rest position, this lbeing .shown in :solid lines in Figs. 4: rand 9.. 4and Abroken lines in Fig. 3.

Thus the proportioning of the parts is preferably such that when the key is depressed the extension 32 bears against the upper stop bar 28, and the tail 22 bears against the top bar 28, at which time, however, the head has not risen suiiciently to reach the sound producing means. When the head continues rising by inertia until it strikes the sound producing means, the tail 22 moves downwardly toward but does not reach the bottom stop bar 30. For this reason, and also because of the immediate drop of the hammer, there is no damping of the vibration at 26.

The keys and hammers are preferably molded out of a suitable plastic. For ease in molding it is preferably a thermoplastic material, although a thermosetting material could be employed. The key i2 and extension I4 are preferably molded out of a single piece of white plastic. Referring to Fig. 4, the black key 34 and its extension 36 are preferably molded out of a single piece of black plastic. However, we have also made keys in which the key portion is molded separately from Jthe extension, the two being subsequently overlapped and cemented together. In that case the extensions may all be of one color. The hammer with its head and tail is also preferably molded in one piece, and in this case the color is, of course, immaterial.

The key extension as molded is preferably bifurcated at its rear end, thus providing the spaced walls 32 best shown in Fig. 8. These walls are provided with bearings to receive trunnions 24, which are preferably molded integrally with the hammer. The walls 32 are preferably notched from one edge to the bearings, as is indicated by the notch 38 in Fig. 3. The notches converge toward the bearings to a size smaller than the diameter of the trunnions and bearings, but not much smaller, so that the trunnions may be pressed into the bearings with a snap fit. Thus the parts are readily assembled together and remain in assembled relation.

The keys also are preferably pivoted in the piano with a detachable or snap t. Thus in Fig. 3 it will be seen that the side walls 40 of the key are provided with bearings and with notches 42 leading upwardly from the bottom of the walls to the bearings, said notches converging toward the bearing holes to a dimension somewhat smaller than the diameter of the holes. The pivot or fulcrum may be a rod, but in the present case is a round bead I6 at the upper edge of a flat strip 44. To mount the keys on the strip 44 they are simply pressed downwardly over the beaded edge i6. This does not limit the keys against sideward movement. but that is taken care of by additional means next described.

In Figs. 2 through 6 it will be seen that the strip 44 is riveted or eyeletted to a strip 46 which is preferably made of a suitable bre board or thick, heavyweight cardboard or paperboard. The latter is secured edgewise beneath the keyboard, and in effect the assembly of two strips comprises an edgewise strip with a fulcrum rod at the top. The upper edge of the strip 46 is recessed to form projections which fit between the side walls of the keys, thus locating the keys against sideward movement. This is best shown in Fig. 6, in which it will be seen that strip 46 is notched or castellated along its upper edge, thus forming recesses 48 which receive the side walls of the white keys and the side walls 50 of the immediately adjacent black keys. Of course, there is adequate clearance for free action of the 4 keys, and as is shown, the side walls of the keys are made smooth and straight, such that the keys may bear against one another without appreciable friction. However, the locating notches avoid the possibility of all of the keys throughout the keyboard being moved wholly in one direction or the other, with excess cumulative clearance space at one end or the other of the keyboard.

The paperboard strip 46 may be secured in position in a number 0f ways. As here illustrated it is strongly secured by mounting it with a mortise and tenon connection on a thick paperboard or fibre board bottom wall 52 forming a part of the instrument case and located beneath the keyboard. As is best shown in Fig. 6, the strip 46 is recessed to provide tongues or tenons 54, and the bottom wall 52 is slotted or mortised to tightly receive the tenons 54. The parts are glued together, thus forming a sturdy, rigid structure.

The white keys are guided by additional guide means located near their forward ends. This is done by means of a guide strip shown at 56 in Figs. 3, 4 and 7. The strip 56 is notched or castellated on top, thus forming recesses 58 which receive the adjacent side walls of the white keys. The tops of the projections 60 between the recesses 58 are preferably made of suitable height to limit downward movement of the keys when depressed. It was previously mentioned that the ends of the key extensions bear against top stop 28 when the key is depressed, and that limitation is preferred in order to provide maximum movement of the pivot 24 of the hammer. Nevertheless the stops 60 at the forward ends of the keys are useful in protecting the key against excessive downward pressure. Thus a slight clearance may be left between the keys and the stops 60 when the key is depressed gently, but on increased pressure the key yields slightly and then rests on the stops 60. The guide strip 56 thus acts also as a stop strip.

The guide strip 56 is secured in position much as was described for the fulcrum strip 46, it being shaped on bottom to provide tenons 62 which are received in mating slots or mortises in the bottom wall 52 of the instrument. Here again the strip and bottom wall are glued together.

The sound producing means is preferably stringless, and various known constructions may be employed, such as those using plates, tubes, forks, etc. In the present case the sound producing means consists of a metal bar 64 having a series of spring steel rods 66 mounted therein.- The rods may be simple round rods and, of course, Vary in length along the keyboard to produce the desired tones or vibration frequencies. To secure the rods in bar 64 the bar may be provided with a series of holes tting the rods, and

f if desired the stationary ends of the rods may be flattened somewhat before driving the rods through the holes, thus insuring a force fit.

Other details of construction will probably be apparent from study of the drawing. However, it may be pointed out that bar 64 is preferably secured to the top wall 68 (Fig. 3) of the piano case, the latter preferably being made of wood. The front wall 'l0 (Fig. 1) is slid downwardly into position from above, with its ends received in grooves formed in the end walls 12. The lower edge of wall 10 is preferably provided with a heavy sponge rubber strip 14 (Fig. 3) which rests against the white keys just back of the raised .portions of the black keys, and which seals the `4. A key and hammer combination as dened in claim 2, in which the key and extension are molded integrally out of a plastic, and in which the entire hammer is molded integrally out of a plastic.

5. A key and hammer combination as deiined in claim 2, in which the sound producing means is stringless and comprises a bar carrying a series of spring steel rods of varying length, the rods being disposed over the hammers.

6. A key and hammer combination as deiined in claim 1, in which the key and extension are molded integrally out of a plastic, and are hollow, and in which the entire hammer is molded integrally out of a plastic, and is solid, and in which the sound producing means is stringless and comprises a bar carrying a series of spring steel rods of varying length, the rods being disposed over the hammers.

7. A musical instrument comprising a keyboard made up of collaterally disposed horizontal hollow keys each having vertical side walls, a stationary fulcrum strip mounted edgewise beneath said keyboard and extending transversely of the keys, the upper edge of said fulcrum strip being notched or castellated to form projections which lit between the side walls of the keys in order to locate the keys against sideward movement, said fulcrum strip having a continuous stationary fulcrum rod secured along its upper edge, and the side walls of said keys being notched upwardly from the bottom edges to form bearings to receive said fulcrum rod, whereby the keys may be placed downward from above into position on the fulcrum rod.

8. A musical instrument comprising a keyboard made up of collaterally disposed horizontal hollow keys each having vertical side walls, a stationary fulcrum strip mounted edgewise beneath said keyboard and extending transversely of the keys, the upper edge of said fulcrum strip being notched or castellated to form projections which t between the side walls of the keys in order to locate the keys against sideward movement, said fulcrum strip having a continuous stationary fulcrum rod secured along its upper edge, the side walls of said keys being notched upwardly from the bottom edges to form bearings which :dt over said fulcrum rod, whereby the keys may be placed downward from above into position on the fulcrum rod, and said strip having a thickness much greater than the diameter of said rod, and thereby bearing against the inside of the side walls of the keys despite said notches in said side walls.

9. A toy piano comprising a case, and a keyboard made up of collaterally disposed hollow keys each having top, front and side walls, said case having a bottom wall disposed beneath said entire keyboard, a key guide strip mounted edgewise on said bottom wall beneath the forward ends of the keys, the lower edge of said guide strip being recessed to form tenons, and said bottom wall being slotted to receive said tenons, the upper edge of said guide strip being castellated to form projections which t between the side walls of the keys in order to locate the keys against sideward movement, and the tops of the projections of said strip being of suitable height to limit the maximum downward movement of the keys when fully depressed.

10. A musical instrument comprising a keyboard made up of collaterally disposed hollow keys each having top and side walls, a stationary fulcrum strip and a stationary key guide strip each mounted edgewise beneath said keyboard in collateral spaced relation, the key guide strip being located near the ends of the keys, the upper edges of both of said strips being castellated to form projections which fit between the side walls of the keys in order to locate the keys against sideward movement, said fulcrum strip having a continuous stationary fulcrum rod secured along its upper edge, and the side walls of said keys `being notched upwardly from the bottom edges to form bearings which receive said fulcrum rod.

11. A musical instrument comprising a keyboard made up of collaterally disposed hollow keys each having top and side walls, a stationary fulcrum strip and a stationary key guide strip each mounted edgewise beneath said keyboard in collateral spaced relation, the key guide strip being located near the ends of the keys, the upper edges of said strips being castellated to form projections which lit between the side walls of the keys in order to locate the keys against sideward movement, said fulcrum strip having a continuous stationary fulcrum rod secured along its upper edge, the side walls of said keys being notched upwardly from the bottom edges to form bearings which receive said fulcrum rod, said fulcrum strip having a thickness much greater than the diameter of said fulcrum rod and thereby bearing against the inside of the side walls of the keys despite said notches in said side walls, and the tops of the projections of said key guide strip being of suitable height to limit the maximum downward movement of the keys when fully depressed.

12. A key and hammer action for a toy piano, said action comprising a key with a rearward extension, means pivoting the same intermediate the extension and key, the free end of the extension extending upward and pivotally carrying a. hammer the head end of which extends toward the key and above the extension, and the tail end of which extends beyond the pivot of the hammer, sound producing means disposed over said hammer, stop means disposed above the rear end of the extension and hammer, one of said extension and hammer having relatively rigid bearings and the other having a rigid pivot, said bearings being open at one side with a dimension slightly smaller than the diameter of the pivot, whereby the hammer and extension may be pressed into assembled relation with a snap t.

13. A key and hammer action for a musical instrument, said action comprising a key with a rearward extension, fulcrum means pivoting the same intermediate the extension and key, the free end of the extension pivotally carrying a hammer the head end of which extends towards the key, and the tail end of which extends beyond the pivot of the hammer, sound producing means disposed over said hammer, and a stop bar disposed above the rear end of the extension and hammer, whereby when the key is in depressed position the tail bears against the stop bar, the proportioning and disposition of the parts being such that at the latter time the hammer head is not raised sufficiently to reach the sound producing means, and when the hammer head continues rising by inertia it strikes the sound producing means, one of said extension and hammer having a rigid pivot and the other of said extension and hammer having a relatively rigid bearing receiving said pivot, said bearing being open at one side with a dimension slightly smaller than the diameter of the pivot, whereby the hammer and extension may be pressed into assembled relation with a snap fit.

14. A key and hammer action for a musical instrument, said action comprising a key with a rearward extension, fulcrum means pivoting the same intermediate the extension and key, the free end of the extension pivotally carrying a hammer the head end of which extends towards the key, and the tail end of which extends beyond the pivot oi the hammer, sound producing means disposed over said hammer, and a stop bar disposed above the rear end of the extension and hammer, whereby when the key is in depressed position the tail bears against the stop bar, the proportioning and disposition of the parts being such that at the latter time the hammer head is not raised sufficiently to reach the sound producing means, and When the hammer head continues rising by inertia. it strikes the sound prou ducing means, one of said extension and hammer having a rigid pivot and the other of said extension and hammer having a relatively rigid hearing receiving said pivot, said bearing being open at one side with a dimension slightly smaller than the diameter of the pivot, whereby the hammer and extension may be pressed into assembled relation with a snap fit, said key having side walls with fulcrum holes and notches leading convergently upwardly from the bottom of said walls to said holes whereby the key may he pressed downwardly over said fulcrum means with a snap fit.

15. A key and hammer action for a toy piano, said action comprising a key with a rearward extension, rounded fulcrum means pivoting the same intermediate the extension and key, the free end of the extension beingl bi'furcated and pivotally carrying between the extensions thereof a hammer the head end of which extends toward the key, and the tail end of which extends beyond the pivot or the hammer between the bifurcations of the extension, sound producing means disposed over said hammer, a stop bar disposed above the rear end of the extension and hammer, whereby when the key is in depressed position the extension and the tail bear against the stop bar, the proportioning andL disposition of the parts being such that at the latter time the hammer head is not raised suiciently to reach the sound producing means, and when the hammer head continues rising by inertia it strikes the sound producing means, and the bifurcations of said extension having rigid bearings which are opened with the opening converging toward said bearings to a reduced dimension so slightly smaller than the bearing that the pivot may be pressed into the bearing With a snap iit.

16. In a toy piano, a slender generally cylindrical fulcrum or pvot having a horizontal axis and extending' for the length of the key board, an upright support member disposed beneath said i'ulcrum for supporting the same along its length, and a plurality of hollow molded plastic piano each having a main horizontal top wall, a iront wall, and side walls, al1 of said walls being integrally molded out of a suitable molding plastic in a single molding operation, said side Walls having circular fulcrum holes dimensioned to t said fulcrum, and upright notches in said side walls leading upwardly from the bottom edges of said side Walls to said holes, said notches converging toward the holes to a size somewhat smaller than the diameter of the fulcrum, whereby said key may be pressed downwardly over said fulcrum with a snap t, the snap fit resulting solely from the resilience of the material of the side walls themselves.

JEROME D. ENOCHS. ROY M. BROWN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,667,069 Umbriaco Apr. 24, 1928 2,085,766 Loar July 6, 1937 2,279,144 Lohr Apr. 7, 1942 2,469,667 Rhodes May 10, 1949 2,470,659 Sloan May 17, 19.49 2,474,462 Brewer June 28, 1949 2,495,913 Ahern et al. Jan. 31, 1950 FOREIGN PATENTS Number Country Date 478,999 Great Britain Jan. 28, 1938 351,954 italy Aug. 27, 1937 

